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Cryo-EM structure of the replisome reveals multiple interactions coordinating DNA synthesis.

ABSTRACT: We present a structure of the ?650-kDa functional replisome of bacteriophage T7 assembled on DNA resembling a replication fork. A structure of the complex consisting of six domains of DNA helicase, five domains of RNA primase, two DNA polymerases, and two thioredoxin (processivity factor) molecules was determined by single-particle cryo-electron microscopy. The two molecules of DNA polymerase adopt a different spatial arrangement at the replication fork, reflecting their roles in leading- and lagging-strand synthesis. The structure, in combination with biochemical data, reveals molecular mechanisms for coordination of leading- and lagging-strand synthesis. Because mechanisms of DNA replication are highly conserved, the observations are relevant to other replication systems.

SUBMITTER: Kulczyk AW

PROVIDER: S-EPMC5347612 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Cryo-EM structure of the replisome reveals multiple interactions coordinating DNA synthesis.

Kulczyk Arkadiusz W AW Moeller Arne A Meyer Peter P Sliz Piotr P Richardson Charles C CC

Proceedings of the National Academy of Sciences of the United States of America 20170221 10

We present a structure of the ∼650-kDa functional replisome of bacteriophage T7 assembled on DNA resembling a replication fork. A structure of the complex consisting of six domains of DNA helicase, five domains of RNA primase, two DNA polymerases, and two thioredoxin (processivity factor) molecules was determined by single-particle cryo-electron microscopy. The two molecules of DNA polymerase adopt a different spatial arrangement at the replication fork, reflecting their roles in leading- and la ...[more]

PMID: 28223502

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